Physical random access channel configuration for a maximum permissible exposure condition

ABSTRACT

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, receiving, from a base station, one or more configurations for a physical random access channel (PRACH) communication, and transmitting a PRACH communication according to a configuration selected from the one or more configurations based at least in part on the PRACH communication being subject to a maximum permissible exposure (MPE) condition and a rule. The rule may include a parameter that is received from the base station. Numerous other aspects are provided.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is a continuation of U.S. Non-Provisional patentapplication Ser. No. 17/181,897, filed on Feb. 22, 2021, entitled“PHYSICAL RANDOM ACCESS CHANNEL CONFIGURATION FOR A MAXIMUM PERMISSIBLEEXPOSURE CONDITION,” which claims the benefit of U.S. Provisional PatentApplication No. 62/980,668, filed on Feb. 24, 2020, entitled “PHYSICALRANDOM ACCESS CHANNEL CONFIGURATION FOR A MAXIMUM PERMISSIBLE EXPOSURECONDITION,” and assigned to the assignee hereof. The disclosure of theprior application is considered part of and is incorporated by referencein this patent application.

INTRODUCTION

Aspects of the present disclosure generally relate to wirelesscommunication and to techniques and apparatuses for configuring physicalrandom access channel communications.

Wireless communication systems are widely deployed to provide varioustelecommunication services such as telephony, video, data, messaging,and broadcasts. Typical wireless communication systems may employmultiple-access technologies capable of supporting communication withmultiple users by sharing available system resources (e.g., bandwidth,transmit power, and/or the like). Examples of such multiple-accesstechnologies include code division multiple access (CDMA) systems, timedivision multiple access (TDMA) systems, frequency-division multipleaccess (FDMA) systems, orthogonal frequency-division multiple access(OFDMA) systems, single-carrier frequency-division multiple access(SC-FDMA) systems, time division synchronous code division multipleaccess (TD-SCDMA) systems, and Long Term Evolution (LTE).LTE/LTE-Advanced is a set of enhancements to the Universal MobileTelecommunications System (UMTS) mobile standard promulgated by theThird Generation Partnership Project (3GPP).

A wireless communication network may include a number of base stations(BSs) that can support communication for a number of user equipment(UEs). A UE may communicate with a BS via the downlink and uplink.“Downlink” (or “forward link”) refers to the communication link from theBS to the UE, and “uplink” (or “reverse link”) refers to thecommunication link from the UE to the BS. As will be described in moredetail herein, a BS may be referred to as a Node B, a gNB, an accesspoint (AP), a radio head, a transmit receive point (TRP), a new radio(NR) BS, a 5G Node B, and/or the like.

The above multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent user equipment to communicate on a municipal, national,regional, and even global level. NR, which may also be referred to as5G, is a set of enhancements to the LTE mobile standard promulgated bythe 3GPP. NR is designed to better support mobile broadband Internetaccess by improving spectral efficiency, lowering costs, improvingservices, making use of new spectrum, and better integrating with otheropen standards using orthogonal frequency division multiplexing (OFDM)with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL), using CP-OFDMand/or SC-FDM (e.g., also known as discrete Fourier transform spreadOFDM (DFT-s-OFDM)) on the uplink (UL), as well as supportingbeamforming, multiple-input multiple-output (MIMO) antenna technology,and carrier aggregation. However, as the demand for mobile broadbandaccess continues to increase, there exists a need for furtherimprovements in LTE and NR technologies. Preferably, these improvementsshould be applicable to other multiple access technologies and thetelecommunication standards that employ these technologies.

SUMMARY

In some aspects, a method of wireless communication performed by a userequipment (UE) may include receiving, from a base station, one or moreconfigurations for a physical random access channel (PRACH)communication. The method may include transmitting a PRACH communicationaccording to a configuration selected from the one or moreconfigurations based at least in part on the PRACH communication beingsubject to a maximum permissible exposure (MPE) condition and a rule.The rule may include a parameter received from the base station.

In some aspects, a method of wireless communication performed by a basestation may include transmitting, to a UE, one or more configurationsfor a PRACH communication. The method may include transmitting aparameter of a rule that the UE is to use for selecting, based at leastin part on an MPE condition, a configuration of the one or moreconfigurations. The method may include receiving the PRACHcommunication.

In some aspects, a UE for wireless communication may include a memoryand one or more processors coupled to the memory. The memory and the oneor more processors may be configured to receive, from a base station,one or more configurations for a PRACH communication. The memory and theone or more processors may be configured to transmit a PRACHcommunication according to a configuration selected from the one or moreconfigurations based at least in part on the PRACH communication beingsubject to an MPE condition and a rule. The rule may include a parameterreceived from the base station.

In some aspects, a base station for wireless communication may include amemory and one or more processors coupled to the memory. The memory andthe one or more processors may be configured to transmit, to a UE, oneor more configurations for a PRACH communication. The memory and the oneor more processors may be configured to transmit a parameter of a rulethat the UE is to use for selecting, based at least in part on an MPEcondition, a configuration of the one or more configurations, andreceive the PRACH communication.

In some aspects, a non-transitory computer-readable medium may store aset of instructions for wireless communication that includes one or moreinstructions that, when executed by one or more processors of a UE,cause the UE to receive, from a base station, one or more configurationsfor a PRACH communication. The one or more instructions, when executedby one or more processors of the UE, may cause the one or moreprocessors to transmit a PRACH communication according to aconfiguration selected from the one or more configurations based atleast in part on the PRACH communication being subject to an MPEcondition and a rule. The rule may include a parameter received from thebase station.

In some aspects, a non-transitory computer-readable medium may store aset of instructions for wireless communication that includes one or moreinstructions that, when executed by one or more processors of a basestation, cause the base station to transmit, to a UE, one or moreconfigurations for a PRACH communication. The one or more instructions,when executed by one or more processors of the base station, may causethe one or more processors to transmit a parameter of a rule that the UEis to use for selecting, based at least in part on an MPE condition, aconfiguration of the one or more configurations, and receive the PRACHcommunication.

In some aspects, an apparatus for wireless communication may includemeans for receiving, from a base station, one or more configurations fora PRACH communication. The apparatus may include means for transmittinga PRACH communication according to a configuration selected from the oneor more configurations based at least in part on the PRACH communicationbeing subject to an MPE condition and a rule, the rule including aparameter received from the base station.

In some aspects, an apparatus for wireless communication may includemeans for transmitting, to a UE, one or more configurations for a PRACHcommunication. The apparatus may include means for transmitting aparameter of a rule that the UE is to use for selecting, based at leastin part on an MPE condition, a configuration of the one or moreconfigurations, and means for receiving the PRACH communication.

In some aspects, a method of wireless communication, performed by a UE,may include determining a configuration for a PRACH communication basedat least in part on a determination that the PRACH communication issubject to an MPE condition. The method may include transmitting thePRACH communication based at least in part on the configuration.

In some aspects, a method of wireless communication, performed by a basestation, may include determining a configuration for a UE to use for aPRACH communication that is subject to an MPE condition and transmittingthe configuration to the UE. The method may include receiving the PRACHcommunication according to the configuration.

In some aspects, a UE for wireless communication may include a memoryand one or more processors coupled to the memory. The memory and the oneor more processors may be configured to determine a configuration for aPRACH communication based at least in part on a determination that thePRACH communication is subject to an MPE condition, and transmit thePRACH communication based at least in part on the configuration.

In some aspects, a base station for wireless communication may include amemory and one or more processors coupled to the memory. The memory andthe one or more processors may be configured to determine aconfiguration for a UE to use for a PRACH communication that is subjectto an MPE condition, transmit the configuration to the UE, and receivethe PRACH communication according to the configuration.

In some aspects, a non-transitory computer-readable medium may store oneor more instructions for wireless communication. The one or moreinstructions, when executed by one or more processors of a UE, may causethe one or more processors to determine a configuration for a PRACHcommunication based at least in part on a determination that the PRACHcommunication is subject to an MPE condition, and transmit the PRACHcommunication based at least in part on the configuration.

In some aspects, a non-transitory computer-readable medium may store oneor more instructions for wireless communication. The one or moreinstructions, when executed by one or more processors of a base station,may cause the one or more processors to determine a configuration for aUE to use for a PRACH communication that is subject to an MPE condition,transmit the configuration to the UE, and receive the PRACHcommunication according to the configuration.

In some aspects, an apparatus for wireless communication may includemeans for determining a configuration for a PRACH communication based atleast in part on a determination that the PRACH communication is subjectto an MPE condition, and means for transmitting the PRACH communicationbased at least in part on the configuration.

In some aspects, an apparatus for wireless communication may includemeans for determining a configuration for a UE to use for a PRACHcommunication that is subject to an MPE condition, means fortransmitting the configuration to the UE, and means for receiving thePRACH communication according to the configuration.

Aspects generally include a method, apparatus, system, computer programproduct, non-transitory computer-readable medium, user equipment, basestation, wireless communication device, and/or processing system assubstantially described with reference to and as illustrated by thedrawings and specification.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purpose ofillustration and description, and not as a definition of the limits ofthe claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the above-recited features of the present disclosure can beunderstood in detail, a more particular description, briefly summarizedabove, may be had by reference to aspects, some of which are illustratedin the appended drawings. It is to be noted, however, that the appendeddrawings illustrate only certain typical aspects of this disclosure andare therefore not to be considered limiting of its scope, for thedescription may admit to other equally effective aspects. The samereference numbers in different drawings may identify the same or similarelements.

FIG. 1 is a diagram illustrating an example of a wireless communicationnetwork, in accordance with the present disclosure.

FIG. 2 is a diagram illustrating an example of a base station incommunication with a UE in a wireless communication network, inaccordance with the present disclosure.

FIG. 3 is a diagram illustrating an example of a synchronization signal(SS) hierarchy, in accordance with the present disclosure.

FIG. 4A is a diagram illustrating an example of a 4-step random accesschannel (RACH) procedure, in accordance with the present disclosure.

FIG. 4B is a diagram illustrating an example of a 2-step RACH procedure,in accordance with the present disclosure.

FIGS. 5A-5C are diagrams illustrating examples of maximum permissibleexposure (MPE) conditions, in accordance with the present disclosure.

FIG. 6 illustrates an example of physical random access channel (PRACH)configuration for an MPE condition, in accordance with the presentdisclosure.

FIG. 7 is a diagram illustrating an example process performed, forexample, by a UE, in accordance with the present disclosure.

FIG. 8 is a diagram illustrating an example process performed, forexample, by a base station, in accordance with the present disclosure.

FIG. 9 is a diagram illustrating an example process performed, forexample, by a UE, in accordance with the present disclosure.

FIG. 10 is a diagram illustrating an example process performed, forexample, by a base station, in accordance with the present disclosure.

FIG. 11 is a block diagram of an example apparatus for wirelesscommunication, in accordance with the present disclosure.

FIG. 12 is a diagram illustrating an example of a hardwareimplementation for an apparatus employing a processing system, inaccordance with the present disclosure.

FIG. 13 is a diagram illustrating an example of an implementation ofcode and circuitry for an apparatus, in accordance with the presentdisclosure.

FIG. 14 is a block diagram of an example apparatus for wirelesscommunication, in accordance with the present disclosure.

FIG. 15 is a diagram illustrating an example of a hardwareimplementation for an apparatus employing a processing system, inaccordance with the present disclosure.

FIG. 16 is a diagram illustrating an example of an implementation ofcode and circuitry for an apparatus, in accordance with the presentdisclosure.

DETAILED DESCRIPTION

A user equipment (UE) may use a random access channel (RACH) procedureto synchronize with a base station and to establish a radio resourcecontrol (RRC) connection to the base station. This may give the UE thecapability to transmit data to and receive data from the base station.To start the RACH procedure, the UE may transmit a random access channel(RACH) message to the base station to initiate communication with thebase station. The RACH message may be a physical RACH (PRACH)communication, or a communication transmitted on the PRACH. The PRACHcommunication may be a preamble, which is one of multiple patterns orsignatures recognized by the base station. The UE may use the PRACHcommunication to request an uplink allocation from the base station.

Some governing bodies have placed restrictions on a peak radiated powerthat can be directed toward a human body. These restrictions aresometimes referred to as maximum permissible exposure (MPE) limitations,MPE constraints, and/or the like. A PRACH communication may be subjectto an MPE condition. If the MPE condition causes the PRACH communicationto fail, the device transmitting the PRACH communication will wasteresources and latency will increase.

According to various aspects described herein, a UE may transmit thePRACH communication with an alternative PRACH configuration if the PRACHcommunication is subject to an MPE condition. For example, the UE maytransmit the PRACH communication with a PRACH format, a PRACH length, aset of PRACH sequences, a bandwidth, or a combination thereof that isdifferent than if the PRACH communication is not subject to an MPEcondition.

In some aspects, the UE may use a rule for selecting a PRACHconfiguration if the PRACH communication is subject to an MPE condition.The UE may receive a parameter for the rule from a base station. Forexample, the UE may receive an updated signal strength threshold as atrigger for when the UE is to use the alternative PRACH configuration.By dynamically providing a parameter for the rule for selecting a PRACHconfiguration, the base station may exercise more flexibility inhandling MPE conditions at the UE.

Various aspects of the disclosure are described more fully hereinafterwith reference to the accompanying drawings. This disclosure may,however, be embodied in many different forms and should not be construedas limited to any specific structure or function presented throughoutthis disclosure. Rather, these aspects are provided so that thisdisclosure will be thorough and complete, and will fully convey thescope of the disclosure to those skilled in the art. Based on theteachings herein one skilled in the art should appreciate that the scopeof the disclosure is intended to cover any aspect of the disclosuredisclosed herein, whether implemented independently of or combined withany other aspect of the disclosure. For example, an apparatus may beimplemented or a method may be practiced using any number of the aspectsset forth herein. In addition, the scope of the disclosure is intendedto cover such an apparatus or method which is practiced using otherstructure, functionality, or structure and functionality in addition toor other than the various aspects of the disclosure set forth herein. Itshould be understood that any aspect of the disclosure disclosed hereinmay be embodied by one or more elements of a claim.

Several aspects of telecommunication systems will now be presented withreference to various apparatuses and techniques. These apparatuses andtechniques will be described in the following detailed description andillustrated in the accompanying drawings by various blocks, modules,components, circuits, steps, processes, and/or algorithms (collectivelyreferred to as “elements”). These elements may be implemented usinghardware, software, or combinations thereof. Whether such elements areimplemented as hardware or software depends upon the particularapplication and design constraints imposed on the overall system.

It should be noted that while aspects may be described herein usingterminology commonly associated with a 5G or NR radio access technology(RAT), aspects of the present disclosure can be applied to other RATs,such as a 3G RAT, a 4G RAT, and/or a RAT subsequent to 5G (e.g., 6G).

FIG. 1 is a diagram illustrating an example of a wireless network 100,in accordance with the present disclosure. The wireless network 100 maybe or may include elements of a 5G (NR) network and/or an LTE network,among other examples. The wireless network 100 may include a number ofbase stations 110 (shown as BS 110 a, BS 110 b, BS 110 c, and BS 110 d)and other network entities. A base station (BS) is an entity thatcommunicates with user equipment (UEs) and may also be referred to as abase station, a NR BS, a Node B, a gNB, a 5G node B (NB), an accesspoint, a transmit receive point (TRP), or the like. Each BS may providecommunication coverage for a particular geographic area. In 3GPP, theterm “cell” can refer to a coverage area of a BS and/or a BS subsystemserving this coverage area, depending on the context in which the termis used.

A BS may provide communication coverage for a macro cell, a pico cell, afemto cell, and/or another type of cell. A macro cell may cover arelatively large geographic area (e.g., several kilometers in radius)and may allow unrestricted access by UEs with service subscription. Apico cell may cover a relatively small geographic area and may allowunrestricted access by UEs with service subscription. A femto cell maycover a relatively small geographic area (e.g., a home) and may allowrestricted access by UEs having association with the femto cell (e.g.,UEs in a closed subscriber group (CSG)). A BS for a macro cell may bereferred to as a macro BS. A BS for a pico cell may be referred to as apico BS. A BS for a femto cell may be referred to as a femto BS or ahome BS. In the example shown in FIG. 1 , a BS 110 a may be a macro BSfor a macro cell 102 a, a BS 110 b may be a pico BS for a pico cell 102b, and a BS 110 c may be a femto BS for a femto cell 102 c. A BS maysupport one or multiple (e.g., three) cells. The terms “eNB”, “basestation”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” maybe used interchangeably herein.

In some examples, a cell may not necessarily be stationary, and thegeographic area of the cell may move according to the location of amobile BS. In some examples, the BSs may be interconnected to oneanother and/or to one or more other BSs or network nodes (not shown) inthe wireless network 100 through various types of backhaul interfacessuch as a direct physical connection or a virtual network, using anysuitable transport network.

Wireless network 100 may also include relay stations. A relay station isan entity that can receive a transmission of data from an upstreamstation (e.g., a BS or a UE) and send a transmission of the data to adownstream station (e.g., a UE or a BS). A relay station may also be aUE that can relay transmissions for other UEs. In the example shown inFIG. 1 , a relay BS 110 d may communicate with macro BS 110 a and a UE120 d in order to facilitate communication between BS 110 a and UE 120d. A relay BS may also be referred to as a relay station, a relay basestation, and/or a relay.

Wireless network 100 may be a heterogeneous network that includes BSs ofdifferent types, such as macro BSs, pico BSs, femto BSs, and/or relayBSs. These different types of BSs may have different transmit powerlevels, different coverage areas, and different impacts on interferencein wireless network 100. For example, macro BSs may have a high transmitpower level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relayBSs may have lower transmit power levels (e.g., 0.1 to 2 watts).

A network controller 130 may couple to a set of BSs and may providecoordination and control for these BSs. Network controller 130 maycommunicate with the BSs via a backhaul. The BSs may also communicatewith one another, e.g., directly or indirectly via a wireless orwireline backhaul.

UEs 120 (e.g., 120 a, 120 b, 120 c) may be dispersed throughout wirelessnetwork 100, and each UE may be stationary or mobile. A UE may also bereferred to as an access terminal, a terminal, a mobile station, asubscriber unit, and/or a station. A UE may be a cellular phone (e.g., asmart phone), a personal digital assistant (PDA), a wireless modem, awireless communication device, a handheld device, a laptop computer, acordless phone, a wireless local loop (WLL) station, a tablet, a camera,a gaming device, a netbook, a smartbook, an ultrabook, a medical deviceor equipment, biometric sensors/devices, wearable devices (smartwatches, smart clothing, smart glasses, smart wrist bands, smart jewelry(e.g., a smart ring, a smart bracelet)), an entertainment device (e.g.,a music or video device, or a satellite radio), a vehicular component orsensor, smart meters/sensors, industrial manufacturing equipment, aglobal positioning system device, or any other suitable device that isconfigured to communicate via a wireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolvedor enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEsinclude, for example, robots, drones, remote devices, sensors, meters,monitors, and/or location tags, that may communicate with a basestation, another device (e.g., remote device), or some other entity. Awireless node may provide, for example, connectivity for or to a network(e.g., a wide area network such as Internet or a cellular network) via awired or wireless communication link. Some UEs may be consideredInternet-of-Things (IoT) devices, and/or may be implemented as may beimplemented as NB-IoT (narrowband internet of things) devices. Some UEsmay be considered a Customer Premises Equipment (CPE). UE 120 may beincluded inside a housing that houses components of UE 120, such asprocessor components and/or memory components. In some aspects, theprocessor components and the memory components may be coupled together.For example, the processor components (e.g., one or more processors) andthe memory components (e.g., a memory) may be operatively coupled,communicatively coupled, electronically coupled, and/or electricallycoupled.

In general, any number of wireless networks may be deployed in a givengeographic area. Each wireless network may support a particular RAT andmay operate on one or more frequencies. A RAT may also be referred to asa radio technology or an air interface. A frequency may also be referredto as a carrier or a frequency channel. Each frequency may support asingle RAT in a given geographic area in order to avoid interferencebetween wireless networks of different RATs. In some cases, NR or 5G RATnetworks may be deployed.

In some aspects, two or more UEs 120 (e.g., shown as UE 120 a and UE 120e) may communicate directly using one or more sidelink channels (e.g.,without using a base station 110 as an intermediary to communicate withone another). For example, UEs 120 may communicate using peer-to-peer(P2P) communications, device-to-device (D2D) communications, avehicle-to-everything (V2X) protocol (e.g., which may include avehicle-to-vehicle (V2V) protocol or a vehicle-to-infrastructure (V2I)protocol), and/or a mesh network. In some aspects, UE 120 may performscheduling operations, resource selection operations, and/or otheroperations described elsewhere herein as being performed by the basestation 110.

The electromagnetic spectrum is often subdivided, based onfrequency/wavelength, into various classes, bands, channels, etc. In 5GNR two initial operating bands have been identified as frequency rangedesignations FR1 (410 MHz-7.125 GHz) and FR2 (24.25 GHz-52.6 GHz). Itshould be understood that although a portion of FR1 is greater than 6GHz, FR1 is often referred to (interchangeably) as a “Sub-6 GHz” band invarious documents and articles. A similar nomenclature issue sometimesoccurs with regard to FR2, which is often referred to (interchangeably)as a “millimeter wave” band in documents and articles, despite beingdifferent from the extremely high frequency (EHF) band (30 GHz-300 GHz)which is identified by the International Telecommunications Union (ITU)as a “millimeter wave” (mmWave) band.

The frequencies between FR1 and FR2 are often referred to as mid-bandfrequencies. Recent 5G NR studies have identified an operating band forthese mid-band frequencies as frequency range designation FR3 (7.125GHz-24.25 GHz). Frequency bands falling within FR3 may inherit FR1characteristics and/or FR2 characteristics, and thus may effectivelyextend features of FR1 and/or FR2 into mid-band frequencies. Inaddition, higher frequency bands are currently being explored to extend5G NR operation beyond 52.6 GHz. For example, three higher operatingbands have been identified as frequency range designations FR4a or FR4-1(52.6 GHz-71 GHz), FR4 (52.6 GHz-114.25 GHz), and FR5 (114.25 GHz-300GHz). Each of these higher frequency bands falls within the EHF band.

With the above aspects in mind, unless specifically stated otherwise, itshould be understood that the term “sub-6 GHz” or the like if usedherein may broadly represent frequencies that may be less than 6 GHz,may be within FR1, or may include mid-band frequencies. Further, unlessspecifically stated otherwise, it should be understood that the term“millimeter wave” or the like if used herein may broadly representfrequencies that may include mid-band frequencies, may be within FR2,FR4, FR4-a or FR4-1, and/or FR5, or may be within the EHF band.

As shown in FIG. 1 , UE 120 may include a communication manager 140. Asdescribed in more detail elsewhere herein, communication manager 140 maydetermine a configuration for a PRACH communication based at least inpart on a determination that the PRACH communication is subject to anMPE condition. Communication manager 140 may transmit the PRACHcommunication based at least in part on the configuration. Additionally,or alternatively, the communication manager 140 may perform one or moreother operations described herein.

Similarly, base station 110 may include a communication manager 150. Asdescribed in more detail elsewhere herein, communication manager 150 maydetermine a configuration for a UE to use for a PRACH communication thatis subject to an MPE condition, and transmit the configuration to theUE. Communication manager 150 may receive the PRACH communicationaccording to the configuration. Additionally, or alternatively,communication manager 150 may perform one or more other operationsdescribed herein.

As shown in FIG. 1 , UE 120 may include a communication manager 140. Asdescribed in more detail elsewhere herein, communication manager 140 mayreceive, from a base station, one or more configurations for a PRACHcommunication. Communication manager 140 may transmit a PRACHcommunication according to a configuration selected from the one or moreconfigurations based at least in part on the PRACH communication beingsubject to an MPE condition and a rule, the rule including a parameterreceived from the base station. Additionally, or alternatively,communication manager 140 may perform one or more other operationsdescribed herein.

Similarly, the base station 110 may include a communication manager 150.As described in more detail elsewhere herein, communication manager 150may transmit, to a UE, one or more configurations for a PRACHcommunication. Communication manager 150 may transmit a parameter of arule that the UE is to use for selecting, based at least in part on anMPE condition, a configuration of the one or more configurations.Communication manager 150 may receive the PRACH communication.Additionally, or alternatively, communication manager 150 may performone or more other operations described herein.

As indicated above, FIG. 1 is provided merely as an example. Otherexamples may differ from what is described with regard to FIG. 1 .

FIG. 2 shows a block diagram of a design 200 of base station 110 and UE120, which may be one of the base stations and one of the UEs in FIG. 1. Base station 110 may be equipped with T antennas 234 a through 234 t,and UE 120 may be equipped with R antennas 252 a through 252 r, where ingeneral T≥1 and R≥1.

At base station 110, a transmit processor 220 may receive data from adata source 212 for one or more UEs, select one or more modulation andcoding schemes (MCS) for each UE based at least in part on channelquality indicators (CQIs) received from the UE, process (e.g., encodeand modulate) the data for each UE based at least in part on the MCS(s)selected for the UE, and provide data symbols for all UEs. Transmitprocessor 220 may also process system information (e.g., for semi-staticresource partitioning information (SRPI) and/or the like) and controlinformation (e.g., CQI requests, grants, upper layer signaling, and/orthe like) and provide overhead symbols and control symbols. Transmitprocessor 220 may also generate reference symbols for reference signals(e.g., the cell-specific reference signal (CRS)) and synchronizationsignals (e.g., the primary synchronization signal (PSS) and secondarysynchronization signal (SSS)). A transmit (TX) multiple-inputmultiple-output (MIMO) processor 230 may perform spatial processing(e.g., precoding) on the data symbols, the control symbols, the overheadsymbols, and/or the reference symbols, if applicable, and may provide Toutput symbol streams to T modulators (MODs) 232 a through 232 t. Eachmodulator 232 may process a respective output symbol stream (e.g., forOFDM and/or the like) to obtain an output sample stream. Each modulator232 may further process (e.g., convert to analog, amplify, filter, andupconvert) the output sample stream to obtain a downlink signal. Tdownlink signals from modulators 232 a through 232 t may be transmittedvia T antennas 234 a through 234 t, respectively. According to variousaspects described in more detail below, the synchronization signals canbe generated with location encoding to convey additional information.

At UE 120, antennas 252 a through 252 r may receive the downlink signalsfrom base station 110 and/or other base stations and may providereceived signals to demodulators (DEMODs) 254 a through 254 r,respectively. Each demodulator 254 may condition (e.g., filter, amplify,downconvert, and digitize) a received signal to obtain input samples.Each demodulator 254 may further process the input samples (e.g., forOFDM and/or the like) to obtain received symbols. A MIMO detector 256may obtain received symbols from all R demodulators 254 a through 254 r,perform MIMO detection on the received symbols if applicable, andprovide detected symbols. A receive processor 258 may process (e.g.,demodulate and decode) the detected symbols, provide decoded data for UE120 to a data sink 260, and provide decoded control information andsystem information to a controller/processor 280. A channel processormay determine reference signal received power (RSRP), received signalstrength indicator (RSSI), reference signal received quality (RSRQ),and/or CQI. In some aspects, one or more components of UE 120 may beincluded in a housing.

On the uplink, at UE 120, a transmit processor 264 may receive andprocess data from a data source 262 and control information (e.g., forreports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) fromcontroller/processor 280. Transmit processor 264 may also generatereference symbols for one or more reference signals. The symbols fromtransmit processor 264 may be precoded by a TX MIMO processor 266 ifapplicable, further processed by modulators 254 a through 254 r (e.g.,for DFT-s-OFDM, CP-OFDM, and/or the like), and transmitted to basestation 110. At base station 110, the uplink signals from UE 120 andother UEs may be received by antennas 234, processed by demodulators232, detected by a MIMO detector 236 if applicable, and furtherprocessed by a receive processor 238 to obtain decoded data and controlinformation sent by UE 120. Receive processor 238 may provide thedecoded data to a data sink 239 and the decoded control information tocontroller/processor 240. Base station 110 may include communicationunit 244 and communicate to network controller 130 via communicationunit 244. Network controller 130 may include communication unit 294,controller/processor 290, and memory 292.

Controller/processor 240 of base station 110, controller/processor 280of UE 120, and/or any other component(s) of FIG. 2 may perform one ormore techniques associated with PRACH configuration for an MPEcondition, as described in more detail elsewhere herein. For example,controller/processor 240 of base station 110, controller/processor 280of UE 120, and/or any other component(s) of FIG. 2 may perform or directoperations of, for example, process 700 of FIG. 7 , process 800 of FIG.8 , and/or other processes as described herein. Memories 242 and 282 maystore data and program codes for base station 110 and UE 120,respectively. A scheduler 246 may schedule UEs for data transmission onthe downlink and/or uplink.

In some aspects, UE 120 may include means for determining aconfiguration for a PRACH communication based at least in part on adetermination that the PRACH communication is subject to an MPEcondition, and/or means for transmitting the PRACH communication basedat least in part on the configuration. Additionally, or alternatively,UE 120 may include means for performing one or more other operationsdescribed herein. In some aspects, such means may include communicationmanager 140. Additionally, or alternatively, such means may include oneor more components of UE 120 described in connection with FIG. 2 .

In some aspects, base station 110 may include means for determining aconfiguration for a UE to use for a PRACH communication that is subjectto an MPE condition, means for transmitting the configuration to the UE,and/or means for receiving the PRACH communication according to theconfiguration. Additionally, or alternatively, base station 110 mayinclude means for performing one or more other operations describedherein. In some aspects, such means may include communication manager150. In some aspects, such means may include one or more components ofbase station 110 described in connection with FIG. 2 .

In some aspects, UE 120 may include means for receiving, from a basestation, one or more configurations for a PRACH communication, and/ormeans for transmitting a PRACH communication according to aconfiguration selected from the one or more configurations based atleast in part on the PRACH communication being subject to an MPEcondition and a rule. The rule may include a parameter received from thebase station. The means for UE 120 to perform operations describedherein may include, for example, one or more of antenna 252, demodulator254, MIMO detector 256, receive processor 258, transmit processor 264,TX MIMO processor 266, modulator 254, controller/processor 280, ormemory 282. In some aspects, UE 120 may include means for receiving,from the base station, the rule for selecting the configuration.

In some aspects, base station 110 may include means for transmitting, toa UE, one or more configurations for a PRACH communication, and/or meansfor transmitting a parameter of a rule that the UE is to use forselecting, based at least in part on an MPE condition, a configurationof the one or more configurations, and/or means for receiving the PRACHcommunication. The means for base station 110 to perform operationsdescribed herein may include, for example, one or more of transmitprocessor 220, TX MIMO processor 230, modulator 232, antenna 234,demodulator 232, MIMO detector 236, receive processor 238,controller/processor 240, memory 242, or scheduler 246. In some aspects,base station 110 includes means for transmitting the rule to the UE.

As indicated above, FIG. 2 is provided merely as an example. Otherexamples may differ from what is described with regard to FIG. 2 .

FIG. 3 is a diagram illustrating an example 300 of a synchronizationsignal (SS) hierarchy, in accordance with the present disclosure. Asshown in FIG. 3 , the SS hierarchy may include an SS burst set 305,which may include multiple SS bursts 310, shown as SS burst 0 through SSburst N−1, where N is a maximum number of repetitions of the SS burst310 that may be transmitted by the base station. As further shown, eachSS burst 310 may include one or more SS blocks (SSBs) 315, shown as SSB0 through SSB M−1, where M is a maximum number of SSBs 315 that can becarried by an SS burst 310. In some aspects, different SSBs 315 may bebeam-formed differently (e.g., transmitted using different beams), andmay be used for beam management, beam selection, and/or the like (e.g.,as part of an initial network access procedure). An SS burst set 305 maybe periodically transmitted by a wireless node (e.g., base station 110),such as every X milliseconds, as shown in FIG. 3 . In some aspects, anSS burst set 305 may have a fixed or dynamic length, shown as Ymilliseconds in FIG. 3 . In some aspects, wide broadcast SSB beams maybe used for RACH procedures.

In some aspects, an SSB 315 may include resources that carry a primarysynchronization signal (PSS) 320, a secondary synchronization signal(SSS) 325, and/or a physical broadcast channel (PBCH) 330. In someaspects, multiple SSBs 315 are included in an SS burst 310 (e.g., withtransmission on different beams), and the PSS 320, the SSS 325, and/orthe PBCH 330 may be the same across each SSB 315 of the SS burst 310. Insome aspects, a single SSB 315 may be included in an SS burst 310. Insome aspects, SSB 315 may be at least four symbols (e.g., OFDM symbols)in length, where each symbol carries one or more of the PSS 320 (e.g.,occupying one symbol), SSS 325 (e.g., occupying one symbol), and/or thePBCH 330 (e.g., occupying two symbols). In some aspects, an SSB 315 maybe referred to as an SS/PBCH block.

In some aspects, the symbols of an SSB 315 are consecutive, as shown inFIG. 3 . In some aspects, the symbols of an SSB 315 are non-consecutive.Similarly, in some aspects, one or more SSBs 315 of SS burst 310 may betransmitted in consecutive radio resources (e.g., consecutive symbols)during one or more slots. Additionally, or alternatively, one or moreSSBs 315 of SS burst 310 may be transmitted in non-consecutive radioresources.

In some aspects, SS bursts 310 may have a burst period, and SSBs 315 ofSS burst 310 may be transmitted by a wireless node (e.g., base station110) according to the burst period. In this case, SSBs 315 may berepeated during each SS burst 310. In some aspects, SS burst set 305 mayhave a burst set periodicity, whereby SS bursts 310 of SS burst set 305are transmitted by the wireless node according to the fixed burst setperiodicity. In other words, SS bursts 310 may be repeated during eachSS burst set 305.

In some aspects, an SSB 315 may include an SSB index that corresponds toa beam used to carry the SSB 315. A UE 120 may monitor for and/ormeasure SSBs 315 using different receive (Rx) beams during an initialnetwork access procedure. Based at least in part on the monitoringand/or measuring, UE 120 may indicate one or more SSBs 315 with a bestsignal parameter (e.g., an RSRP parameter and/or the like) to a basestation 110. Base station 110 and UE 120 may use the one or moreindicated SSBs 315 to select one or more beams to be used forcommunication between base station 110 and UE 120 (e.g., for a RACHprocedure and/or the like). In some aspects, a UE may use an RSRP of anSSB broadcast to help determine a configuration for a PRACHcommunication.

As indicated above, FIG. 3 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 3 .

As explained earlier, a UE may transmit a RACH message to a base stationto initiate communication with the base station. The RACH message may bewhat the UE first transmits when the UE is powered on. The RACH messagemay be transmitted on a PRACH and may be referred to more generally as aPRACH communication. The UE may use the PRACH communication to requestan uplink allocation from the base station.

A PRACH communication may include a PRACH sequence (also referred to asa PRACH preamble or a PRACH preamble sequence) that may be used todifferentiate UEs. The UE may use a PRACH format to determine the PRACHsequence and/or transmission properties of the PRACH sequence. The UEmay receive an initial PRACH configuration in a transmission from thebase station and use the initial PRACH configuration for transmittingthe PRACH communication. The PRACH communication may initiate a RACHprocedure to obtain the uplink allocation.

FIG. 4A is a diagram illustrating an example 400 of a 4-step RACHprocedure and FIG. 4B is a diagram illustrating an example 402 of a2-step RACH procedure. In each example, a UE is performing a RACHprocedure with a base station.

In LTE and NR, the 4-step RACH procedure may be a RACH procedure with afour message (msg1, msg2, msg3, msg4) handshake between the UE and thebase station. The UE may transmit msg1 with a PRACH preamble to the basestation on a PRACH, as an example of a PRACH communication. The PRACHcommunication may follow a PRACH configuration selected based on a rulefor selecting PRACH configurations when the UE is subject to an MPEcondition. The base station may transmit msg2 to the UE on a physicaldownlink control channel (PDCCH) and a physical downlink shared channel(PDSCH). Msg2 may include a random access response. The UE may transmitmsg3 on a physical uplink shared channel (PUSCH). Msg3 may include acontention request and device information. The base station may transmitmsg4 on the PDCCH and the PDSCH. Msg4 may include a contentionresolution. The contention request and contention resolution relate toresolving contention from multiple UEs that happen to use the same PRACHpreamble.

In NR, the 2-step RACH procedure is another RACH procedure. In the2-step procedure, a base station broadcasts system information and SSBinformation to UEs. A UE may transmit a PRACH preamble as part of a msgAmessage to the base station, as an example of a PRACH communication. ThePRACH communication may follow a PRACH configuration selected based on arule for selecting PRACH configurations when the UE is subject to an MPEcondition. The rule may apply whether the PRACH communication is a msg3of a 4-step RACH procedure or a msgA of a 2-step RACH procedure. MsgAmay also include a payload. The base station may process the preamble,detect the preamble, and process the payload. The base station may senda response in msgB. Msg1 and msg3 of the 4-step RACH may be consideredto be collapsed into the msgA, and msg2 and msg4 are considered to becollapsed into msgB.

Depending on the PRACH configuration selected due to an MPE condition,the UE may transmit the PRACH communication with a PRACH format, a PRACHlength, a set of PRACH sequences, a bandwidth, or a combination thereofthat is different than if the PRACH communication is not subject to anMPE condition. As indicated above, FIGS. 4A and 4B are provided as twoexamples of a RACH procedure. Other examples may differ from what isdescribed with regard to FIGS. 4A and 4B.

FIGS. 5A-5C are diagrams illustrating an example 500 of an MPEcondition. FIG. 5A shows a BS 510 and a UE 520 that may communicate witheach other.

As shown in FIG. 5A, UE 520 and BS 510 may have the capability tocommunicate via one or more beams. In some cases, an uplink beam, suchas beam 530, may be a mmWave beam that carries a communication in themmWave frequency band. The communication may be a PRACH communication,such as a msg1 preamble (4-step RACH procedure) or a msg1 preamble(2-step RACH procedure), as described in connection with FIGS. 4A and4B. When transmitting in the mmWave frequency band, a transmitter mayuse a higher antenna gain than when transmitting in the sub-6 GHzfrequency band. As a result, the effective isotropic radiated power(EIRP), which represents the radiated power in a particular direction(e.g., the direction of the beam), may be higher for mmWavecommunications than for sub-6 GHz communications. Some governing bodieshave placed restrictions on the peak EIRP that can be directed towardthe human body. These restrictions are sometimes referred to as MPElimitations or MPE constraints.

An MPE condition or event may be due to a blocking scenario, shown byFIG. 5B, where a human body blocks or obstructs beam 530 from an antennasubarray of UE 520. In another scenario shown by FIG. 5C, a human handmay be positioned near an antenna subarray of UE 520. Beam 530 may betransmitting a threshold level of EIRP towards the hand and thus UE 520is subject to an MPE condition. By contrast, beam 532 is nottransmitting through a human body part and thus is not subject to an MPEcondition. Additionally, or alternatively, the MPE condition may be dueto the position of another body part of the user, such as the user'sface, head, ear, and/or leg.

Beam 530 is an uplink beam that may match a downlink beam so as to forma reciprocal beam pair. When UE 520 is subject to an MPE condition, adownlink beam of the reciprocal beam pair may be suitable for use by UE520 to receive communications from BS 510, and may have better beamconditions (e.g., a stronger beam) as compared to other downlink beams.However, beam 530 of the reciprocal beam pair may not be permitted fortransmission of communications by UE 520 due to the MPE condition. Forexample, the downlink beam may not be subject to an MPE constraintbecause an EIRP level of a transmission by stations 510 may subside bythe time the transmission reaches UE 520 and/or the user's hand or otherbody part. However, uplink beam 130 may be subject to an MPE constraint(e.g., maximum transmit power) because an EIRP level of a transmissionby UE 520 may exceed a permitted EIRP level due to the close proximityof UE 520 and the hand or other body part.

In such a case, it may be beneficial for UE 520 and/or BS 510 to use afirst beam for uplink communications and a second beam for downlinkcommunications, where the first beam (e.g., a UE uplink beam or a BSuplink beam) does not form a reciprocal beam pair with the second beam(e.g., a UE downlink beam or a BS downlink beam). In some aspects, UE520 may select non-reciprocal UE beams to communicate with BS 510 evenif BS 510 is using reciprocal BS beams to communicate with UE 510. Forexample, UE uplink beam may be included in another cluster of beams. Bychoosing distinct UE uplink and UE downlink beams, the UE may improveperformance while satisfying an MPE constraint.

UE 520 may determine, for a candidate UE uplink beam, such as beam 530,a maximum transmit power due to an MPE constraint (e.g., an MPElimitation, an MPE restriction). As used herein, the maximum transmitpower due to the MPE constraint may be referred to as an MPE-constrainedmaximum transmit power. That is, UE 520 may not use a transmit powerthat exceeds the MPE-constrained maximum power. In some aspects, theMPE-constrained maximum transmit power for a candidate UE uplink beammay vary over time due to, for example, movement of UE 520 and/or arotation of UE 520. Thus, UE 520 may determine the MPE-constrainedmaximum transmit power for a candidate UE uplink beam at a specific timeand/or for a specific time period.

In some aspects, UE 520 may determine the MPE-constrained maximumtransmit power for a candidate UE uplink beam based at least in part onan EIRP value for the candidate UE uplink beam, a maximum or peak EIRPvalue stored by UE 520 (e.g., as dictated by a governing body, asspecified in a wireless communication standard, as configured for UE520) and/or a determination of whether the candidate UE uplink beam isdirected toward a body (e.g., a human body). For example, if thecandidate UE uplink beam is not directed toward a body, then UE 520 mayset the MPE-constrained maximum transmit power to a maximum transmitpower value for UE 520, which may be stored by UE 520, may be determinedbased at least in part on a class of UE 520 or specified by a wirelesscommunication standard. However, if the candidate UE uplink beam isdirected toward a body, then UE 520 may set the MPE-constrained maximumtransmit power based at least in part on a determined EIRP value for thecandidate UE uplink beam and/or a maximum permitted EIRP value.

As shown by FIGS. 5B and 5C, UE 520 may prepare to transmit the PRACHcommunication to BS 510 but uplink beam 530 may be subject to an MPEcondition and may not be able to select another beam for the PRACHcommunication. If UE 520 does not account for the MPE condition, thePRACH communication may fail. This failure may cause the UE to wastesignaling resources and increase latency for establishing a connectionto BS 510.

According to various aspects described herein, UE 520 may transmit thePRACH communication with an alternative PRACH configuration if UE 520determines that the PRACH communication is subject to an MPE condition.For example, UE 520 may transmit the PRACH communication with a PRACHformat, a PRACH length, a set of PRACH sequences, a bandwidth, or acombination thereof that is different than if the PRACH communication isnot subject to an MPE condition. UE 520 may select an alternative PRACHconfiguration according to a rule. For example, UE 520 may select analternative PRACH format if a signal strength satisfies a signalstrength threshold. Due to changing conditions, this threshold or otherrule parameter may need to be adjusted. In some aspects, BS 510 maytransmit the threshold or other parameter to UE 520. In this way, BS 510may successfully receive the PRACH communication and other PRACHmessages. As a result, UE 520 and BS 510 may avoid wasting resources andavoid increasing latency for failed PRACH communications.

As indicated above, FIGS. 5A-5C are provided as examples. Other examplesare possible and may differ from what is described in connection withFIGS. 5A-5C.

FIG. 6 illustrates an example 600 of PRACH configuration for an MPEcondition, in accordance with the present disclosure. FIG. 6 shows abase station (BS) 610 (e.g., BS 110 depicted in FIGS. 1 and 2 ) and a UE620 (e.g., UE 120 depicted in FIGS. 1 and 2 ) that may communicate withone another.

As shown by reference number 630, BS 610 may determine a configurationfor UE 620 to use for a PRACH communication that is subject to an MPEcondition. The configuration may specify a PRACH format, a PRACH length,a set of PRACH sequences, a bandwidth, or a combination thereof that isdifferent than if the PRACH communication is not subject to an MPEcondition. For example, the configuration may specify that the PRACHcommunication is to have a different PRACH format that is reduced insize or a number of fields so that an overall transmission time (andoverall transmit power) is lower than for a regularly used PRACH format.In some aspects, the configuration may specify that the PRACHcommunication is to have a shorter PRACH length and/or fewer PRACHsequences. In some aspects, the configuration may specify that the PRACHcommunication is to be transmitted at another frequency or in anotherbandwidth.

As shown by reference number 635, BS 610 may transmit the configurationto UE 620, and UE 620 may receive the configuration. BS 610 may transmitthe configuration via a remaining minimum system information (RMSI)message or another system information message.

As shown by reference number 640, UE 620 may determine a configurationfor a PRACH communication based at least in part on a determination thata PRACH communication is subject to an MPE condition. UE 620 maydetermine if the PRACH communication is subject to an MPE condition byusing one or more sensors (e.g., ultrasonic proximity sensor, thermalproximity sensor, diode sensor, and/or the like) to determine that ahuman or a body part of a human is nearby and/or may be in a beam pathbetween UE 620 and BS 610. UE 620 may compare detection information,obtained by the one or more sensors, and a proximity threshold todetermine whether there is an MPE condition. UE 620 may also make an MPEcondition determination based at least in part on a frequency range, aspatial filter configuration, a power density, a transmit power, alength of the PRACH communication, and/or the like for the PRACHcommunication. The configuration for the PRACH communication may be theconfiguration received from BS 610, or UE 620 may use a configurationincluded in stored configuration information.

In some aspects, UE 620 may determine the configuration based at leastin part on a combination of an MPE constraint and an SSB-based RSRP. Forexample, UE 620 may determine the configuration based at least in parton a result of comparing an RSRP for an SSB broadcast and an RSRPthreshold that applies to an MPE constraint (e.g., when there is bodyproximity for an uplink transmission panel of UE 620 and/or a directionof the UE beam). The RSRP threshold that applies to an MPE constraintmay be different (e.g., lower) than an RSRP threshold that does notapply to an MPE constraint. For example, the RSRP threshold that appliesto an MPE constraint may be the RSRP threshold that does not apply tothe MPE constraint minus a threshold offset. The threshold offset maybe, for example, 5 decibels (dBs). A difference between the RSRPthreshold that applies to an MPE constraint and the RSRP threshold thatdoes not apply to the MPE may be based at least in part on a frequencyband for the PRACH communication. In some aspects, UE 620 may receive anRSRP threshold from BS 610. In other words, UE 620 may choose anotherPRACH configuration with more transmission time or more transmit powerif a strength of an SSB broadcast does not satisfy a threshold signallevel, and that other PRACH configuration may be a first configurationif there is no MPE constraint and a second configuration if there is anMPE constraint.

In some aspects, UE 620 may determine the configuration by selecting aconfiguration from among multiple configurations, where one or moreconfigurations apply to an MPE constraint and one or more configurationsdo not apply to the MPE constraint. In some aspects, UE 620 may beconfigured with rules for determining a configuration. A rule mayspecify conditions for selecting a configuration, or more specifically,a PRACH length, a PRACH format, a set of PRACH sequences, a bandwidth,and/or a combination thereof. For example, a rule may specify that aconfiguration with a shorter PRACH length and fewer PRACH sequences isto be used when the PRACH communication is subject to an MPE conditionand a rule that an RSRP of an SSB broadcast does not satisfy aparticular parameter, such as an RSRP threshold. UE 620 may determinethe rules from stored configuration information or receive the rulesand/or other parameters (e.g., proximity threshold, EIRP value)associated with a rule from BS 610 via system information (e.g., RMSI).In sum, UE 620 may determine a configuration for a PRACH communicationthat may meet an MPE constraint and still lead to a successfulconnection with BS 610.

As shown by reference number 645, UE 620 may transmit the PRACHcommunication based at least in part on the configuration. For example,UE 620 may transmit the PRACH communication with a length of 1millisecond rather than 2 milliseconds. In another example, UE 620transmits the PRACH communication with a set of fewer PRACH sequences.

As indicated above, FIG. 6 is provided as an example. Other examples arepossible and may differ from what is described in connection with FIG. 6.

FIG. 7 is a diagram illustrating an example process 700 performed, forexample, by a UE, in accordance with the present disclosure. Exampleprocess 700 is an example where the UE (e.g., UE 120 depicted in FIGS. 1and 2 , UE 620 depicted in FIG. 6 ) performs operations associated withPRACH configuration for an MPE condition.

As shown in FIG. 7 , in some aspects, process 700 may includedetermining a configuration for a PRACH communication based at least inpart on a determination that the PRACH communication is subject to anMPE condition (block 710). For example, the UE (e.g., using receiveprocessor 258, transmit processor 264, controller/processor 280, memory282) may determine a configuration for a PRACH communication based atleast in part on a determination that the PRACH communication is subjectto an MPE condition, as described above.

As further shown in FIG. 7 , in some aspects, process 700 may includetransmitting the PRACH communication based at least in part on theconfiguration (block 720). For example, the UE (e.g., using receiveprocessor 258, transmit processor 264, controller/processor 280, memory282) may transmit the PRACH communication based at least in part on theconfiguration, as described above.

Process 700 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the configuration specifies one or more of a PRACHcommunication length, a PRACH format, a set of PRACH sequences, a PRACHbandwidth, or a combination of two or more of the PRACH communicationlength, the PRACH format, the set of PRACH sequences, or the PRACHbandwidth.

In a second aspect, alone or in combination with the first aspect,process 700 includes receiving the configuration from a base station.

In a third aspect, alone or in combination with one or more of the firstand second aspects, receiving the configuration includes receiving theconfiguration via a remaining minimum system information message.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, determining the configuration includesselecting the configuration from among a plurality of configurations,and the plurality of configurations includes a configuration thatapplies to an MPE constraint and a configuration that does not apply toan MPE constraint.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, determining the configuration includesdetermining the configuration based at least in part on a combination ofan MPE constraint and an RSRP of an SSB communication.

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, determining the configuration includesdetermining the configuration based at least in part on a result ofcomparing the RSRP of the SSB communication and an RSRP threshold thatapplies to the MPE constraint.

In a seventh aspect, alone or in combination with one or more of thefirst through sixth aspects, the RSRP threshold that applies to the MPEconstraint is based at least in part on an RSRP threshold that does notapply to the MPE constraint and a threshold offset.

In an eighth aspect, alone or in combination with one or more of thefirst through seventh aspects, process 700 includes receiving the RSRPthreshold that applies to the MPE constraint from a base station.

In a ninth aspect, alone or in combination with one or more of the firstthrough eighth aspects, determining the configuration includesdetermining the configuration based at least in part on the rule.

Although FIG. 7 shows example blocks of process 700, in some aspects,process 700 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 7 .Additionally, or alternatively, two or more of the blocks of process 700may be performed in parallel.

FIG. 8 is a diagram illustrating an example process 800 performed, forexample, by a base station, in accordance with the present disclosure.Example process 800 is an example where the base station (e.g., BS 110depicted in FIGS. 1 and 2 , BS 610 depicted in FIG. 6 ) performsoperations associated with PRACH configuration for an MPE condition.

As shown in FIG. 8 , in some aspects, process 800 may includedetermining a configuration for UE to use for a PRACH communication thatis subject to an MPE condition (block 810). For example, the basestation (e.g., using transmit processor 220, receive processor 238,controller/processor 240, memory 242) may determine a configuration fora UE to use for a PRACH communication that is subject to an MPEcondition, as described above.

As further shown in FIG. 8 , in some aspects, process 800 may includetransmitting the configuration to the UE (block 820). For example, thebase station (e.g., using transmit processor 220, receive processor 238,controller/processor 240, memory 242) may transmit the configuration tothe UE, as described above.

As further shown in FIG. 8 , in some aspects, process 800 may includereceiving the PRACH communication according to the configuration (block830). For example, the base station (e.g., using transmit processor 220,receive processor 238, controller/processor 240, memory 242) may receivethe PRACH communication according to the configuration, as describedabove.

Process 800 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the configuration specifies one or more of a PRACHcommunication length, a PRACH format, a set of PRACH sequences, a PRACHbandwidth, or a combination of two or more of the PRACH communicationlength, the PRACH format, the set of PRACH sequences, or the PRACHbandwidth.

In a second aspect, alone or in combination with the first aspect,transmitting the configuration includes transmitting the configurationvia a remaining minimum system information message.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the configuration is based at least in part on acombination of an MPE constraint for the PRACH communication and an RSRPof an SSB communication received by the UE.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, process 800 includes transmitting an RSRPthreshold for an MPE constraint to the UE.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, the RSRP threshold for the MPE constraint isbased at least in part on a non-MPE constraint RSRP threshold and athreshold offset.

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, process 800 includes transmitting a rule topermit the UE to determine the configuration.

Although FIG. 8 shows example blocks of process 800, in some aspects,process 800 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 8 .Additionally, or alternatively, two or more of the blocks of process 800may be performed in parallel.

FIG. 9 is a diagram illustrating an example process 900 performed, forexample, by a UE, in accordance with the present disclosure. Exampleprocess 900 is an example where the UE (e.g., UE 120 depicted in FIGS. 1and 2 , UE 620 depicted in FIG. 6 ) performs operations associated withPRACH configuration for an MPE condition.

As shown in FIG. 9 , in some aspects, process 900 may include receiving,from a base station, one or more configurations for a PRACHcommunication (block 910). For example, the UE (e.g., using receiveprocessor 258, transmit processor 264, controller/processor 280, memory282) may receive, from a base station, one or more configurations for aPRACH communication, as described above.

As further shown in FIG. 9 , in some aspects, process 900 may includetransmitting a PRACH communication according to a configuration selectedfrom the one or more configurations based at least in part on the PRACHcommunication being subject to an MPE condition and a rule (block 920).For example, the UE (e.g., using receive processor 258, transmitprocessor 264, controller/processor 280, memory 282) may transmit aPRACH communication according to a configuration selected from the oneor more configurations based at least in part on the PRACH communicationbeing subject to an MPE condition and a rule, as described above. Insome aspects, the rule may include a parameter received from the basestation, as described above.

Process 900 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the configuration specifies one or more of a PRACHcommunication length, a PRACH format, a set of PRACH sequences, a PRACHbandwidth, or a combination of two or more of the PRACH communicationlength, the PRACH format, the set of PRACH sequences, or the PRACHbandwidth.

In a second aspect, alone or in combination with the first aspect,receiving the one or more configurations includes receiving the one ormore configurations via an RMSI message.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the one or more configurations include aconfiguration that applies to an MPE constraint and a configuration thatdoes not apply to an MPE constraint.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, the configuration is selected based atleast in part on a combination of an MPE constraint and an RSRP of anSSB communication.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, the configuration is selected based at least inpart on a result of comparing the RSRP of the SSB communication and anRSRP threshold that applies to the MPE constraint.

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, the RSRP threshold that applies to the MPEconstraint is based at least in part on an RSRP threshold that does notapply to the MPE constraint, and a threshold offset.

In a seventh aspect, alone or in combination with one or more of thefirst through sixth aspects, the parameter received from the basestation includes the RSRP threshold that applies to the MPE constraint.

In an eighth aspect, alone or in combination with one or more of thefirst through seventh aspects, process 900 includes receiving, from thebase station, the rule for selecting the configuration.

Although FIG. 9 shows example blocks of process 900, in some aspects,process 900 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 9 .Additionally, or alternatively, two or more of the blocks of process 900may be performed in parallel.

FIG. 10 is a diagram illustrating an example process 1000 performed, forexample, by a base station, in accordance with the present disclosure.Example process 1000 is an example where the base station (e.g., BS 110depicted in FIGS. 1 and 2 , BS 610 depicted in FIG. 6 ) performsoperations associated with PRACH configuration for an MPE condition.

As shown in FIG. 10 , in some aspects, process 1000 may includetransmitting, to a UE, one or more configurations for a PRACHcommunication (block 1010). For example, the base station (e.g., usingtransmit processor 220, receive processor 238, controller/processor 240,memory 242) may transmit, to a UE, one or more configurations for aPRACH communication, as described above.

As further shown in FIG. 10 , in some aspects, process 1000 may includetransmitting a parameter of a rule that the UE is to use for selecting,based at least in part on an MPE condition, a configuration of the oneor more configurations (block 1020). For example, the base station(e.g., using transmit processor 220, receive processor 238,controller/processor 240, memory 242) may transmit a parameter of a rulethat the UE is to use for selecting, based at least in part on an MPEcondition, a configuration of the one or more configurations, asdescribed above.

As further shown in FIG. 10 , in some aspects, process 1000 may includereceiving the PRACH communication (block 1030). For example, the basestation (e.g., using transmit processor 220, receive processor 238,controller/processor 240, memory 242) may receive the PRACHcommunication, as described above.

Process 1000 may include additional aspects, such as any single aspector any combination of aspects described below and/or in connection withone or more other processes described elsewhere herein.

In a first aspect, each configuration of the one or more configurationsspecifies one or more of a PRACH communication length, a PRACH format, aset of PRACH sequences, a PRACH bandwidth, or a combination of two ormore of the PRACH communication length, the PRACH format, the set ofPRACH sequences, or the PRACH bandwidth.

In a second aspect, alone or in combination with the first aspect,transmitting the one or more configurations includes transmitting theone or more configurations via an RMSI message.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the parameter is an RSRP threshold that applies toan MPE constraint.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, the RSRP threshold that applies to the MPEconstraint is based at least in part on an RSRP threshold that does notapply to the MPE constraint and a threshold offset.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, process 1000 includes transmitting the rule tothe UE.

Although FIG. 10 shows example blocks of process 1000, in some aspects,process 1000 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 10 .Additionally, or alternatively, two or more of the blocks of process1000 may be performed in parallel.

FIG. 11 is a block diagram of an example apparatus 1100 for wirelesscommunication. The apparatus 1100 may be a UE, or a UE may includeapparatus 1100. In some aspects, apparatus 1100 includes a receptioncomponent 1102 and a transmission component 1104, which may be incommunication with one another (for example, via one or more busesand/or one or more other components). As shown, apparatus 1100 maycommunicate with another apparatus 1106 (such as a UE (e.g., UE 120 e,among other examples), a base station (e.g., BS 110 a, BS 110 d, amongother examples), or another wireless communication device) usingreception component 1102 and transmission component 1104. As furthershown, apparatus 1100 may include one or more of adetermination/selection component 1108, among other examples.

In some aspects, apparatus 1100 may be configured to perform one or moreoperations described herein in connection with FIGS. 1-6 . Additionallyor alternatively, apparatus 1100 may be configured to perform one ormore processes described herein, such as process 700 of FIG. 7 , process900 of FIG. 9 , or a combination thereof. In some aspects, apparatus1100 and/or one or more components shown in FIG. 11 may include one ormore components of the network node described above in connection withFIG. 2 . Additionally, or alternatively, one or more components shown inFIG. 11 may be implemented within one or more components described abovein connection with FIG. 2 . Additionally or alternatively, one or morecomponents of the set of components may be implemented at least in partas software stored in a memory. For example, a component (or a portionof a component) may be implemented as instructions or code stored in anon-transitory computer-readable medium and executable by a controlleror a processor to perform the functions or operations of the component.

Reception component 1102 may receive communications, such as referencesignals, control information, data communications, or a combinationthereof, from apparatus 1106. Reception component 1102 may providereceived communications to one or more other components of apparatus1100. In some aspects, reception component 1102 may perform signalprocessing on the received communications (such as filtering,amplification, demodulation, analog-to-digital conversion,demultiplexing, deinterleaving, de-mapping, equalization, interferencecancellation, or decoding, among other examples), and may provide theprocessed signals to the one or more other components of apparatus 1106.In some aspects, reception component 1102 may include one or moreantennas, a demodulator, a MIMO detector, a receive processor, acontroller/processor, a memory, or a combination thereof, of the networknode described above in connection with FIG. 2 .

Transmission component 1104 may transmit communications, such asreference signals, control information, data communications, or acombination thereof, to apparatus 1106. In some aspects, one or moreother components of apparatus 1106 may generate communications and mayprovide the generated communications to transmission component 1104 fortransmission to apparatus 1106. In some aspects, transmission component1104 may perform signal processing on the generated communications (suchas filtering, amplification, modulation, digital-to-analog conversion,multiplexing, interleaving, mapping, or encoding, among other examples),and may transmit the processed signals to apparatus 1106. In someaspects, transmission component 1104 may include one or more antennas, amodulator, a transmit MIMO processor, a transmit processor, acontroller/processor, a memory, or a combination thereof, of the networknode described above in connection with FIG. 2 . In some aspects,transmission component 1104 may be co-located with reception component1102 in a transceiver.

Determination/selection component 1108 may determine a configuration fora PRACH communication based at least in part on a determination that thePRACH communication is subject to an MPE condition. Transmissioncomponent 1104 may transmit the PRACH communication based at least inpart on the configuration.

Reception component 1102 may receive, from apparatus 1106, one or moreconfigurations for a PRACH communication. Transmission component 1104may transmit a PRACH communication according to a configuration selectedfrom the one or more configurations based at least in part on the PRACHcommunication being subject to an MPE condition and a rule, the ruleincluding a parameter received from the base station.Determination/selection component 1108 may select the configurationbased at least in part on a combination of an MPE constraint and an RSRPof an SSB communication.

The number and arrangement of components shown in FIG. 11 are providedas an example. In practice, there may be additional components, fewercomponents, different components, or differently arranged componentsthan those shown in FIG. 11 . Furthermore, two or more components shownin FIG. 11 may be implemented within a single component, or a singlecomponent shown in FIG. 11 may be implemented as multiple, distributedcomponents. Additionally or alternatively, a set of (one or more)components shown in FIG. 11 may perform one or more functions describedas being performed by another set of components shown in FIG. 11 .

FIG. 12 is a diagram illustrating an example 1200 of a hardwareimplementation for an apparatus 1205 employing a processing system 1210.Apparatus 1205 may be a UE.

Processing system 1210 may be implemented with a bus architecture,represented generally by bus 1215. Bus 1215 may include any number ofinterconnecting buses and bridges depending on the specific applicationof processing system 1210 and the overall design constraints. Bus 1215links together various circuits including one or more processors and/orhardware components, represented by processor 1220, the illustratedcomponents, and computer-readable medium/memory 1225. Bus 1215 may alsolink various other circuits, such as timing sources, peripherals,voltage regulators, power management circuits, and/or the like.

Processing system 1210 may be coupled to a transceiver 1230. Transceiver1230 is coupled to one or more antennas 1235. Transceiver 1230 providesa means for communicating with various other apparatuses over atransmission medium. Transceiver 1230 receives a signal from the one ormore antennas 1235, extracts information from the received signal, andprovides the extracted information to processing system 1210,specifically reception component 1102. In addition, transceiver 1230receives information from processing system 1210, specificallytransmission component 1104, and generates a signal to be applied to oneor more antennas 1235 based at least in part on the receivedinformation.

Processing system 1210 includes a processor 1220 coupled to acomputer-readable medium/memory 1225. Processor 1220 is responsible forgeneral processing, including the execution of software stored oncomputer-readable medium/memory 1225. The software, when executed byprocessor 1220, causes processing system 1210 to perform the variousfunctions described herein for any particular apparatus.Computer-readable medium/memory 1225 may also be used for storing datathat is manipulated by processor 1220 when executing software.Processing system 1210 further includes at least one of the illustratedcomponents. The components may be software modules running in processor1220, resident/stored in computer readable medium/memory 1225, one ormore hardware modules coupled to processor 1220, or some combinationthereof.

In some aspects, processing system 1210 may be a component of basestation 110 (e.g., BS 110 a, BS 110 d, among other examples) and mayinclude the memory 242 and/or at least one of TX MIMO processor 230, RXprocessor 238, and/or controller/processor 240. In some aspects,processing system 1210 may be a component of UE 120 (e.g., UE 120 eamong other examples) and may include controller/processor 280, TXprocessor 264, TX MIMO processor 266, and/or RX processor 258. In someaspects, apparatus 1205 for wireless communication includes means fordetermining a configuration for a PRACH communication based at least inpart on a determination that the PRACH communication is subject to anMPE condition, and/or means for transmitting the PRACH communicationbased at least in part on the configuration, among other examples. Insome aspects, apparatus 1205 may include means for receiving, from abase station, one or more configurations for a PRACH communication,and/or means for transmitting a PRACH communication according to aconfiguration selected from the one or more configurations based atleast in part on the PRACH communication being subject to an MPEcondition and a rule, the rule including a parameter received from thebase station. The aforementioned means may be one or more of theaforementioned components of apparatus 1100 and/or the processing system1210 of apparatus 1205 configured to perform the functions recited bythe aforementioned means. As described elsewhere herein, processingsystem 1210 may include TX MIMO processor 230, receive processor 238,and/or controller/processor 240. In one configuration, theaforementioned means may be TX MIMO processor 230, receive processor238, and/or the controller/processor 240 configured to perform thefunctions and/or operations recited herein.

FIG. 12 is provided as an example. Other examples may differ from whatis described in connection with FIG. 12 .

FIG. 13 is a diagram illustrating an example 1300 of an implementationof code and circuitry for an apparatus 1305. Apparatus 1305 may be a UE.

As further shown in FIG. 13 , the apparatus may include circuitry fordetermining a configuration for a PRACH communication based at least inpart on a determination that the PRACH communication is subject to anMPE condition (circuitry 1320). For example, the apparatus may includecircuitry to enable the apparatus to determine the configuration basedat least in part on a result of comparing the RSRP of the SSBcommunication and an SSB threshold that applies to the MPE constraint.

As further shown in FIG. 13 , the apparatus may include circuitry fortransmitting the PRACH communication based at least in part on theconfiguration (circuitry 1325). For example, the apparatus may includecircuitry to enable the apparatus to transmit a PRACH communicationaccording to a configuration selected from the one or moreconfigurations based at least in part on the PRACH communication beingsubject to an MPE condition and a rule, the rule including a parameterreceived from the base station.

As further shown in FIG. 13 , the apparatus may include circuitry forreceiving one or more configurations for a PRACH communication(circuitry 1330). For example, the apparatus may include circuitry toenable the apparatus to receive one or more configurations for a PRACHcommunication. The apparatus may include circuitry to enable theapparatus to use a configuration that specifies one or more of a PRACHcommunication length, a PRACH format, a set of PRACH sequences, a PRACHbandwidth, or a combination of two or more of the PRACH communicationlength, the PRACH format, the set of PRACH sequences, or the PRACHbandwidth.

As further shown in FIG. 13 , the apparatus may include, stored incomputer-readable medium 1225, code for determining configuration for aPRACH communication based at least in part on a determination that thePRACH communication is subject to an MPE condition (code 1335). Forexample, the apparatus may include code that, when executed by theprocessor 1220, may cause processor 1220 to determine a configurationfor a PRACH communication based at least in part on a determination thatthe PRACH communication is subject to an MPE condition.

As further shown in FIG. 12 , the apparatus may include, stored incomputer-readable medium 1225, code for transmitting the PRACHcommunication based at least in part on the configuration (code 1340).For example, the apparatus may include code that, when executed byprocessor 1220, may cause processor 1220 to cause transceiver 1230 totransmit the PRACH communication based at least in part on theconfiguration.

As further shown in FIG. 12 , the apparatus may include, stored incomputer-readable medium 1225, code for transmitting a PRACHcommunication according to a configuration selected from the one or moreconfigurations based at least in part on the PRACH communication beingsubject to an MPE condition and a rule, the rule including that isreceived from the base station (code 1340). For example, the apparatusmay include code that, when executed by processor 1220, may causeprocessor 1220 to cause transceiver 1230 to transmit the PRACHcommunication according to a configuration selected from the one or moreconfigurations based at least in part on the PRACH communication beingsubject to an MPE condition and a rule, the rule including a parameterreceived from the base station.

As further shown in FIG. 12 , the apparatus may include, stored incomputer-readable medium 1225, code for receiving one or moreconfigurations for a PRACH communication (code 1345). For example, theapparatus may include code that, when executed by processor 1220, maycause processor 1220 to cause transceiver 1230 to receive one or moreconfigurations for a PRACH communication.

FIG. 13 is provided as an example. Other examples may differ from whatis described in connection with FIG. 13 .

FIG. 14 is a block diagram of an example apparatus 1400 for wirelesscommunication. The apparatus 1400 may be a UE, or a UE may includeapparatus 1400. In some aspects, apparatus 1400 includes a receptioncomponent 1402 and a transmission component 1404, which may be incommunication with one another (for example, via one or more busesand/or one or more other components). As shown, apparatus 1400 maycommunicate with another apparatus 1406 (such as a UE (e.g., UE 120 e,among other examples), a base station (e.g., BS 110 a, BS 110 d, amongother examples), or another wireless communication device) usingreception component 1402 and transmission component 1404. As furthershown, apparatus 1400 may include one or more of adetermination/selection component 1408, among other examples.

In some aspects, apparatus 1400 may be configured to perform one or moreoperations described herein in connection with FIGS. 1-6 . Additionallyor alternatively, apparatus 1400 may be configured to perform one ormore processes described herein, such as process 800 of FIG. 8 , process1000 of FIG. 10 , or a combination thereof. In some aspects, apparatus1400 and/or one or more components shown in FIG. 14 may include one ormore components of the network node described above in connection withFIG. 2 . Additionally, or alternatively, one or more components shown inFIG. 14 may be implemented within one or more components described abovein connection with FIG. 2 . Additionally or alternatively, one or morecomponents of the set of components may be implemented at least in partas software stored in a memory. For example, a component (or a portionof a component) may be implemented as instructions or code stored in anon-transitory computer-readable medium and executable by a controlleror a processor to perform the functions or operations of the component.

Reception component 1402 may receive communications, such as referencesignals, control information, data communications, or a combinationthereof, from apparatus 1406. Reception component 1402 may providereceived communications to one or more other components of apparatus1400. In some aspects, reception component 1402 may perform signalprocessing on the received communications (such as filtering,amplification, demodulation, analog-to-digital conversion,demultiplexing, deinterleaving, de-mapping, equalization, interferencecancellation, or decoding, among other examples), and may provide theprocessed signals to the one or more other components of apparatus 1406.In some aspects, reception component 1402 may include one or moreantennas, a demodulator, a MIMO detector, a receive processor, acontroller/processor, a memory, or a combination thereof, of the networknode described above in connection with FIG. 2 .

Transmission component 1404 may transmit communications, such asreference signals, control information, data communications, or acombination thereof, to apparatus 1406. In some aspects, one or moreother components of apparatus 1406 may generate communications and mayprovide the generated communications to transmission component 1404 fortransmission to apparatus 1406. In some aspects, transmission component1404 may perform signal processing on the generated communications (suchas filtering, amplification, modulation, digital-to-analog conversion,multiplexing, interleaving, mapping, or encoding, among other examples),and may transmit the processed signals to apparatus 1406. In someaspects, transmission component 1404 may include one or more antennas, amodulator, a transmit MIMO processor, a transmit processor, acontroller/processor, a memory, or a combination thereof, of the networknode described above in connection with FIG. 2 . In some aspects,transmission component 1404 may be co-located with reception component1402 in a transceiver.

Determination/selection component 1408 may determine a configuration fora UE to use for a PRACH communication that is subject to an MPEcondition. Transmission component 1404 may transmit the configuration tothe UE. Reception component 1402 may the PRACH communication accordingto the configuration.

Transmission component 1404 may transmit, to a UE, one or moreconfigurations for a PRACH communication. Transmission component 1404may transmit a parameter of a rule that the UE is to use for selecting,based at least in part on an MPE condition, a configuration of the oneor more configurations. Reception component 1402 may receive the PRACHcommunication. Determination/selection component 1408 may determine theparameter from among other parameters based at least in part on a UEcapability and/or traffic conditions.

The number and arrangement of components shown in FIG. 14 are providedas an example. In practice, there may be additional components, fewercomponents, different components, or differently arranged componentsthan those shown in FIG. 14 . Furthermore, two or more components shownin FIG. 14 may be implemented within a single component, or a singlecomponent shown in FIG. 14 may be implemented as multiple, distributedcomponents. Additionally or alternatively, a set of (one or more)components shown in FIG. 14 may perform one or more functions describedas being performed by another set of components shown in FIG. 14 .

FIG. 15 is a diagram illustrating an example 1500 of a hardwareimplementation for an apparatus 1505 employing a processing system 1510.Apparatus 1505 may be a base station.

Processing system 1510 may be implemented with a bus architecture,represented generally by bus 1515. Bus 1515 may include any number ofinterconnecting buses and bridges depending on the specific applicationof processing system 1510 and the overall design constraints. Bus 1515links together various circuits including one or more processors and/orhardware components, represented by processor 1520, the illustratedcomponents, and computer-readable medium/memory 1525. Bus 1515 may alsolink various other circuits, such as timing sources, peripherals,voltage regulators, power management circuits, and/or the like.

Processing system 1510 may be coupled to a transceiver 1530. Transceiver1530 is coupled to one or more antennas 1535. Transceiver 1530 providesa means for communicating with various other apparatuses over atransmission medium. Transceiver 1530 receives a signal from the one ormore antennas 1535, extracts information from the received signal, andprovides the extracted information to processing system 1510,specifically reception component 1402. In addition, transceiver 1530receives information from processing system 1510, specificallytransmission component 1404, and generates a signal to be applied to oneor more antennas 1535 based at least in part on the receivedinformation.

Processing system 1510 includes a processor 1520 coupled to acomputer-readable medium/memory 1525. Processor 1520 is responsible forgeneral processing, including the execution of software stored oncomputer-readable medium/memory 1525. The software, when executed byprocessor 1520, causes processing system 1510 to perform the variousfunctions described herein for any particular apparatus.Computer-readable medium/memory 1525 may also be used for storing datathat is manipulated by processor 1520 when executing software.Processing system 1510 further includes at least one of the illustratedcomponents. The components may be software modules running in processor1520, resident/stored in computer readable medium/memory 1525, one ormore hardware modules coupled to processor 1520, or some combinationthereof.

In some aspects, processing system 1510 may be a component of basestation 110 (e.g., BS 110 a, BS 110 d, among other examples) and mayinclude the memory 242 and/or at least one of TX MIMO processor 230, RXprocessor 238, and/or controller/processor 240. In some aspects,processing system 1510 may be a component of UE 120 (e.g., UE 120 eamong other examples) and may include controller/processor 280, TXprocessor 264, TX MIMO processor 266, and/or RX processor 258. In someaspects, apparatus 1505 for wireless communication includes means fordetermining a configuration for a UE to use for a PRACH communicationthat is subject to an MPE condition, means for transmitting theconfiguration to the UE, and/or means for receiving the PRACHcommunication according to the configuration, among other examples. Insome aspects, apparatus 1505 may include means for transmitting, to aUE, one or more configurations for a PRACH communication, means fortransmitting a parameter of a rule that the UE is to use for selecting,based at least in part on an MPE condition, a configuration of the oneor more configurations, and/or means for receiving the PRACHcommunication. The aforementioned means may be one or more of theaforementioned components of apparatus 1400 and/or the processing system1510 of apparatus 1505 configured to perform the functions recited bythe aforementioned means. As described elsewhere herein, processingsystem 1510 may include TX MIMO processor 230, receive processor 238,and/or controller/processor 240. In one configuration, theaforementioned means may be TX MIMO processor 230, receive processor238, and/or the controller/processor 240 configured to perform thefunctions and/or operations recited herein.

FIG. 15 is provided as an example. Other examples may differ from whatis described in connection with FIG. 15 .

FIG. 16 is a diagram illustrating an example 1600 of an implementationof code and circuitry for an apparatus 1605. Apparatus 1605 may be abase station.

As further shown in FIG. 16 , the apparatus may include circuitry fordetermining a configuration for a UE to use for a PRACH communicationthat is subject to an MPE condition (circuitry 1620). For example, theapparatus may include circuitry to enable the apparatus to determine aconfiguration for a UE to use for a PRACH communication that is subjectto an MPE condition. The apparatus may include circuitry to enable theapparatus to determine a configuration that specifies one or more of aPRACH communication length, a PRACH format, a set of PRACH sequences, aPRACH bandwidth, or a combination of two or more of the PRACHcommunication length, the PRACH format, the set of PRACH sequences, orthe PRACH bandwidth.

As further shown in FIG. 16 , the apparatus may include circuitry fortransmitting one or more configurations to the UE (circuitry 1625). Forexample, the apparatus may include circuitry to enable the apparatus totransmit the one or more configurations to the UE.

As further shown in FIG. 16 , the apparatus may include circuitry forreceiving the PRACH communication according to the configuration(circuitry 1630). For example, the apparatus may include circuitry toenable the apparatus to receive the PRACH communication according to theconfiguration.

As further shown in FIG. 16 , the apparatus may include circuitry fortransmitting a parameter of a rule that the UE is to use for selecting,based at least in part on an MPE condition, a configuration of the oneor more configurations (circuitry 1635). For example, the apparatus mayinclude circuitry to enable the apparatus to transmit a parameter of arule that the UE is to use for selecting, based at least in part on anMPE condition, a configuration of the one or more configurations.

As further shown in FIG. 16 , the apparatus may include, stored incomputer-readable medium 1525, code for determining a configuration fora UE to use for a PRACH communication that is subject to an MPEcondition (code 1640). For example, the apparatus may include code that,when executed by the processor 1520, may cause processor 1520 todetermine a configuration for a UE to use for a PRACH communication thatis subject to an MPE condition.

As further shown in FIG. 15 , the apparatus may include, stored incomputer-readable medium 1525, code for transmitting one or moreconfigurations to the UE (code 1645). For example, the apparatus mayinclude code that, when executed by processor 1520, may cause processor1520 to cause transceiver 1530 to transmit one or more configurations tothe UE.

As further shown in FIG. 15 , the apparatus may include, stored incomputer-readable medium 1525, code for receiving the PRACHcommunication according to the configuration (code 1650). For example,the apparatus may include code that, when executed by processor 1520,may cause processor 1520 to cause transceiver 1530 to receive the PRACHcommunication according to the configuration.

As further shown in FIG. 15 , the apparatus may include, stored incomputer-readable medium 1525, code for transmitting a parameter of arule that the UE is to use for selecting, based at least in part on anMPE condition, a configuration of the one or more configurations (code1655). For example, the apparatus may include code that, when executedby processor 1520, may cause processor 1520 to cause transceiver 1530 totransmit a parameter of a rule that the UE is to use for selecting,based at least in part on an MPE condition, a configuration of the oneor more configurations.

FIG. 16 is provided as an example. Other examples may differ from whatis described in connection with FIG. 16 .

The foregoing disclosure provides illustration and description, but isnot intended to be exhaustive or to limit the aspects to the preciseform disclosed. Modifications and variations may be made in light of theabove disclosure or may be acquired from practice of the aspects.

The following provides an overview of some Aspects of the presentdisclosure:

Aspect 1: A method of wireless communication performed by a userequipment (UE), comprising: transmitting a PRACH communication selectedfrom the one or more configurations, based at least in part on adetermination that the PRACH communication is subject to a maximumpermissible exposure (MPE) condition and a rule that is based at leastin part on information from the base station.

Aspect 2: The method of Aspect 1, wherein the configuration specifiesone or more of a PRACH communication length, a PRACH format, a set ofPRACH sequences, a PRACH bandwidth, or a combination of two or more ofthe PRACH communication length, the PRACH format, the set of PRACHsequences, or the PRACH bandwidth.

Aspect 3: The method of Aspect 1 or 2, further comprising receiving theconfiguration from a base station.

Aspect 4: The method of Aspect 3, wherein receiving the one or moreconfigurations includes receiving the one or more configurations via aremaining minimum system information message.

Aspect 5: The method of any of Aspects 1-4, wherein determining theconfiguration includes selecting the configuration from among aplurality of configurations, and wherein the plurality of configurationsincludes a configuration that applies to an MPE constraint and aconfiguration that does not apply to an MPE constraint.

Aspect 6: The method of any of Aspects 1-5, wherein determining theconfiguration includes determining the configuration based at least inpart on a combination of an MPE constraint and a reference signalreceive power (RSRP) of a synchronization signal and physical broadcastchannel block (SSB) communication.

Aspect 7: The method of Aspect 6, wherein determining the configurationincludes determining the configuration based at least in part on aresult of comparing the RSRP of the SSB communication and an SSBthreshold that applies to the MPE constraint.

Aspect 8: The method of Aspect 7, wherein the SSB threshold that appliesto the MPE constraint is based at least in part on an SSB threshold thatdoes not apply to the MPE constraint and a threshold offset.

Aspect 9: The method of Aspect 6 or 7, further comprising receiving theSSB threshold that applies to the MPE constraint from a base station.

Aspect 10: The method of any of Aspects 1-9, further comprisingreceiving, from a base station, a rule for determining theconfiguration, and wherein determining the configuration includesdetermining the configuration based at least in part on the rule.

Aspect 11: A method of wireless communication performed by a basestation, comprising: determining a configuration for a user equipment(UE) to use for a physical random access channel (PRACH) communicationthat is subject to a maximum permissible exposure (MPE) condition;transmitting the configuration to the UE; and receiving the PRACHcommunication according to the configuration.

Aspect 12: The method of Aspect 11, wherein the configuration specifiesone or more of a PRACH communication length, a PRACH format, a set ofPRACH sequences, a PRACH bandwidth, or a combination of two or more ofthe PRACH communication length, the PRACH format, the set of PRACHsequences, or the PRACH bandwidth.

Aspect 13: The method of Aspect 11 or 12, wherein transmitting theconfiguration includes transmitting the configuration via a remainingminimum system information message.

Aspect 14: The method of any of Aspects 11-13, wherein the configurationis based at least in part on a combination of an MPE constraint for thePRACH communication and a reference signal receive power (RSRP) of asynchronization signal and physical broadcast channel block (SSB)communication received by the UE.

Aspect 15: The method of any of Aspects 11-14, further comprisingtransmitting a reference signal receive power (RSRP) threshold for anMPE constraint to the UE.

Aspect 16: The method of Aspect 15, wherein the RSRP threshold for theMPE constraint is based at least in part on a non-MPE constraint RSRPthreshold and a threshold offset.

Aspect 17: The method of any of Aspects 11-16, further comprisingtransmitting a rule to permit the UE to select the configuration.

Aspect 18: An apparatus for wireless communication at a device,comprising a processor; memory coupled with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to perform the method of one or more Aspects ofAspects 1-17.

Aspect 19: A device for wireless communication, comprising a memory andone or more processors coupled to the memory, the memory and the one ormore processors configured to perform the method of one or more Aspectsof Aspects 1-17.

Aspect 20: An apparatus for wireless communication, comprising at leastone means for performing the method of one or more Aspects of Aspects1-17.

Aspect 21: A non-transitory computer-readable medium storing code forwireless communication, the code comprising instructions executable by aprocessor to perform the method of one or more Aspects of Aspects 1-17.

Aspect 22: A non-transitory computer-readable medium storing a set ofinstructions for wireless communication, the set of instructionscomprising one or more instructions that, when executed by one or moreprocessors of a device, cause the device to perform the method of one ormore Aspects of Aspects 1-17.

The following provides an overview of some other Aspects of the presentdisclosure:

Aspect 23: A method of wireless communication performed by a userequipment (UE), comprising: receiving, from a base station, one or moreconfigurations for a physical random access channel (PRACH)communication; and transmitting a PRACH communication according to aconfiguration selected from the one or more configurations based atleast in part on the PRACH communication being subject to a maximumpermissible exposure (MPE) condition and a rule, the rule including aparameter received from the base station.

Aspect 24: The method of Aspect 23, wherein the configuration specifiesone or more of a PRACH communication length, a PRACH format, a set ofPRACH sequences, a PRACH bandwidth, or a combination of two or more ofthe PRACH communication length, the PRACH format, the set of PRACHsequences, or the PRACH bandwidth.

Aspect 25: The method of Aspect 23 or 24, wherein receiving the one ormore configurations includes receiving the one or more configurationsvia a remaining minimum system information message.

Aspect 26: The method of any of Aspects 23-25, wherein the one or moreconfigurations include a configuration that applies to an MPE constraintand a configuration that does not apply to an MPE constraint.

Aspect 27: The method of any of Aspects 23-26, wherein the configurationis selected based at least in part on a combination of an MPE constraintand a reference signal receive power (RSRP) of a synchronization signaland physical broadcast channel block (SSB) communication.

Aspect 28: The method of Aspect 27, wherein the configuration isselected based at least in part on a result of comparing the RSRP of theSSB communication and an RSRP threshold that applies to the MPEconstraint.

Aspect 29: The method of Aspect 28, wherein the RSRP threshold thatapplies to the MPE constraint is based at least in part on an RSRPthreshold that does not apply to the MPE constraint, and a thresholdoffset.

Aspect 30: The method of Aspect 28, wherein the parameter received fromthe base station includes the RSRP threshold that applies to the MPEconstraint.

Aspect 31: The method of any of Aspects 23-30, further comprisingreceiving, from the base station, the rule for selecting theconfiguration.

Aspect 32: The method of any of Aspects 23-26, wherein the rulespecifies that the configuration is selected based at least in part on acombination of an MPE constraint and a reference signal receive power(RSRP) of a synchronization signal and physical broadcast channel block(SSB) communication.

Aspect 33: The method of Aspect 32, wherein the rule specifies that theconfiguration is selected based at least in part on a result ofcomparing the RSRP of the SSB communication and an RSRP threshold thatapplies to the MPE constraint.

Aspect 34: The method of Aspect 33, wherein the RSRP threshold thatapplies to the MPE constraint is based at least in part on an RSRPthreshold that does not apply to the MPE constraint, and a thresholdoffset.

Aspect 35: A method of wireless communication performed by a basestation, comprising: transmitting, to a user equipment (UE), one or moreconfigurations for a physical random access channel (PRACH)communication; transmitting a parameter of a rule that the UE is to usefor selecting, based at least in part on a maximum permissible exposure(MPE) condition, a configuration of the one or more configurations; andreceiving the PRACH communication.

Aspect 36: The method of Aspect 33, wherein each configuration of theone or more configurations specifies one or more of a PRACHcommunication length, a PRACH format, a set of PRACH sequences, a PRACHbandwidth, or a combination of two or more of the PRACH communicationlength, the PRACH format, the set of PRACH sequences, or the PRACHbandwidth.

Aspect 37: The method of Aspect 33 or 34, wherein transmitting the oneor more configurations includes transmitting the one or moreconfigurations via a remaining minimum system information message.

Aspect 38: The method of any of Aspects 35-37, wherein the parameter isa reference signal receive power (RSRP) threshold that applies to an MPEconstraint.

Aspect 39: The method of Aspect 38, wherein the RSRP threshold thatapplies to the MPE constraint is based at least in part on an RSRPthreshold that does not apply to the MPE constraint and a thresholdoffset.

Aspect 40: The method of any of Aspects 35-39, further comprisingtransmitting the rule to the UE.

Aspect 41: An apparatus for wireless communication at a device,comprising a processor; memory coupled with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to perform the method of one or more Aspects ofAspects 23-40.

Aspect 42: A device for wireless communication, comprising a memory andone or more processors coupled to the memory, the memory and the one ormore processors configured to perform the method of one or more Aspectsof Aspects 23-40.

Aspect 43: An apparatus for wireless communication, comprising at leastone means for performing the method of one or more Aspects of Aspects23-40.

Aspect 44: A non-transitory computer-readable medium storing code forwireless communication, the code comprising instructions executable by aprocessor to perform the method of one or more Aspects of Aspects 23-40.

Aspect 45: A non-transitory computer-readable medium storing a set ofinstructions for wireless communication, the set of instructionscomprising one or more instructions that, when executed by one or moreprocessors of a device, cause the device to perform the method of one ormore Aspects of Aspects 23-40.

As used herein, the term “component” is intended to be broadly construedas hardware, firmware, and/or a combination of hardware and software. Asused herein, a processor is implemented in hardware, firmware, and/or acombination of hardware and software.

It will be apparent that systems and/or methods described herein may beimplemented in different forms of hardware, firmware, and/or acombination of hardware and software. The actual specialized controlhardware or software code used to implement these systems and/or methodsis not limiting of the aspects. Thus, the operation and behavior of thesystems and/or methods were described herein without reference tospecific software code—it being understood that software and hardwarecan be designed to implement the systems and/or methods based, at leastin part, on the description herein.

As used herein, satisfying a threshold may, depending on the context,refer to a value being greater than the threshold, greater than or equalto the threshold, less than the threshold, less than or equal to thethreshold, equal to the threshold, not equal to the threshold, or thelike.

Even though particular combinations of features are recited in theclaims and/or disclosed in the specification, these combinations are notintended to limit the disclosure of various aspects. In fact, many ofthese features may be combined in ways not specifically recited in theclaims and/or disclosed in the specification. Although each dependentclaim listed below may directly depend on only one claim, the disclosureof various aspects includes each dependent claim in combination withevery other claim in the claim set. As used herein, a phrase referringto “at least one of” a list of items refers to any combination of thoseitems, including single members. As an example, “at least one of: a, b,or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well asany combination with multiples of the same element (e.g., a-a, a-a-a,a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or anyother ordering of a, b, and c).

No element, act, or instruction used herein should be construed ascritical or essential unless explicitly described as such. Also, as usedherein, the articles “a” and “an” are intended to include one or moreitems, and may be used interchangeably with “one or more.” Further, asused herein, the article “the” is intended to include one or more itemsreferenced in connection with the article “the” and may be usedinterchangeably with “the one or more.” Furthermore, as used herein, theterms “set” and “group” are intended to include one or more items (e.g.,related items, unrelated items, or a combination of related andunrelated items), and may be used interchangeably with “one or more.”Where only one item is intended, the phrase “only one” or similarlanguage is used. Also, as used herein, the terms “has,” “have,”“having,” or the like are intended to be open-ended terms. Further, thephrase “based on” is intended to mean “based, at least in part, on”unless explicitly stated otherwise. Also, as used herein, the term “or”is intended to be inclusive when used in a series and may be usedinterchangeably with “and/or,” unless explicitly stated otherwise (e.g.,if used in combination with “either” or “only one of”).

1. An apparatus for wireless communication at a user equipment (UE), theapparatus comprising: one or more memories; and one or more processors,coupled to the one or more memories, configured to cause the UE to:receive a plurality of configurations including: a first configurationspecifying one or more of a first physical random access channel (PRACH)format, a first PRACH length, a first set of PRACH sequences, or a firstPRACH bandwidth, and a second configuration specifying one or more of asecond PRACH format, a second PRACH length, a second set of PRACHsequences, or a second PRACH bandwidth; and transmit a PRACHcommunication according to one of the first configuration or the secondconfiguration based on a maximum permissible exposure (MPE) condition.2. The apparatus of claim 1, wherein the second configuration isdifferent from the first configuration.
 3. The apparatus of claim 1,wherein, to transmit the PRACH communication, the one or more processorsare configured to cause the UE to: transmit the PRACH communicationaccording to one of the first configuration or the second configurationbased on whether the PRACH communication is subject to the MPEcondition.
 4. The apparatus of claim 1, wherein the PRACH communicationis subject to the MPE condition, and wherein the PRACH communication istransmitted according to the first configuration based on the PRACHcommunication being subject to the MPE condition.
 5. The apparatus ofclaim 1, wherein the first configuration specifies the first PRACHformat, wherein the second configuration specifies the second PRACHformat, and wherein the first PRACH format is reduced in size or anumber of fields relative to the second PRACH format.
 6. The apparatusof claim 1, wherein the first configuration specifies the first PRACHlength, wherein the second configuration specifies the second PRACHlength, and wherein the first PRACH length is shorter than the secondPRACH length.
 7. The apparatus of claim 1, wherein the firstconfiguration specifies the first set of PRACH sequences, wherein thesecond configuration specifies the second set of PRACH sequences, andwherein the first set of PRACH sequences has fewer PRACH sequences thanthe second set of PRACH sequences.
 8. The apparatus of claim 1, wherein,to transmit the PRACH communication, the one or more processors areconfigured to cause the UE to: select the first configuration, from theplurality of configurations, based on the MPE condition and a rule thatspecifies one or more conditions for selecting the first configuration,and transmit the PRACH communication based on a selection of the firstconfiguration.
 9. The apparatus of claim 8, wherein the rule specifiesthat a configuration with one or more of a shorter PRACH length or fewerPRACH sequences is to be used when the PRACH communication is subject tothe MPE condition.
 10. The apparatus of claim 8, wherein the one or moreprocessors are further configured to: receive the rule from a networkentity via system information.
 11. The apparatus of claim 1, wherein, totransmit the PRACH communication, the one or more processors areconfigured to cause the apparatus to: determine that the PRACHcommunication is subject to the MPE condition by using one or moresensors to determine that a human or a body part of the human is withina proximity threshold or in a beam path between the UE and a networkentity, and transmit the PRACH communication according to the firstconfiguration based on the PRACH communication being subject to the MPEcondition.
 12. A method of wireless communication performed at anapparatus, comprising: receiving a plurality of configurationsincluding: a first configuration specifying one or more of a firstphysical random access channel (PRACH) format, a first PRACH length, afirst set of PRACH sequences, or a first PRACH bandwidth, and a secondconfiguration specifying one or more of a second PRACH format, a secondPRACH length, a second set of PRACH sequences, or a second PRACHbandwidth; and transmitting a PRACH communication according to one ofthe first configuration or the second configuration based on a maximumpermissible exposure (MPE) condition.
 13. The method of claim 12,wherein transmitting the PRACH communication comprises: transmitting thePRACH communication according to one of the first configuration or thesecond configuration based on whether the PRACH communication is subjectto the MPE condition.
 14. The method of claim 12, wherein the firstconfiguration specifies the first PRACH format, wherein the secondconfiguration specifies the second PRACH format, and wherein the firstPRACH format is reduced in size or a number of fields relative to thesecond PRACH format.
 15. The method of claim 12, wherein the firstconfiguration specifies the first PRACH length, wherein the secondconfiguration specifies the second PRACH length, and wherein the firstPRACH length is shorter than the second PRACH length.
 16. The method ofclaim 12, wherein the first configuration specifies the first set ofPRACH sequences, wherein the second configuration specifies the secondset of PRACH sequences, and wherein the first set of PRACH sequences hasfewer PRACH sequences than the second set of PRACH sequences.
 17. Themethod of claim 12, wherein transmitting the PRACH communicationcomprises: selecting the first configuration, from the plurality ofconfigurations, based on the MPE condition and a rule that specifies oneor more conditions for selecting the first configuration, andtransmitting the PRACH communication based on a selection of the firstconfiguration.
 18. The method of claim 17, wherein the rule specifiesthat a configuration with one or more of a shorter PRACH length or fewerPRACH sequences is to be used when the PRACH communication is subject tothe MPE condition.
 19. The method of claim 17, further comprising:receiving the rule from a network entity via system information.
 20. Themethod of claim 12, wherein transmitting the PRACH communicationcomprises: determining that the PRACH communication is subject to theMPE condition by using one or more sensors to determine that a human ora body part of the human is within a proximity threshold or in a beampath between the apparatus and a network entity, and transmitting thePRACH communication according to the first configuration based on thePRACH communication being subject to the MPE condition.
 21. An apparatusfor wireless communication at a network entity, the apparatuscomprising: one or more memories; and one or more processors, coupled tothe one or more memories, configured to cause the network entity to:transmit a plurality of configurations including: a first configurationspecifying one or more of a first physical random access channel (PRACH)format, a first PRACH length, a first set of PRACH sequences, or a firstPRACH bandwidth, and a second configuration specifying one or more of asecond PRACH format, a second PRACH length, a second set of PRACHsequences, or a second PRACH bandwidth; and receive a PRACHcommunication, according to one of the first configuration or the secondconfiguration based on a maximum permissible exposure (MPE) condition.22. The apparatus of claim 21, wherein, to receive the PRACHcommunication, the one or more processors are configured to cause thenetwork entity to: transmit a parameter of a rule for selecting, basedat least in part on the MPE condition, one of the first configuration orthe second configuration, and receive the PRACH communication accordingto one of the first configuration or the second configuration.
 23. Theapparatus of claim 21, wherein the first configuration specifies thefirst PRACH format, wherein the second configuration specifies thesecond PRACH format, and wherein the first PRACH format is reduced insize or a number of fields relative to the second PRACH format.
 24. Theapparatus of claim 21, wherein the first configuration specifies thefirst PRACH length, wherein the second configuration specifies thesecond PRACH length, and wherein the first PRACH length is shorter thanthe second PRACH length.
 25. The apparatus of claim 21, wherein thefirst configuration specifies the first set of PRACH sequences, whereinthe second configuration specifies the second set of PRACH sequences,and wherein the first set of PRACH sequences has fewer PRACH sequencesthan the second set of PRACH sequences.
 26. A method of wirelesscommunication performed by an apparatus, comprising: transmitting aplurality of configurations including: a first configuration specifyingone or more of a first physical random access channel (PRACH) format, afirst PRACH length, a first set of PRACH sequences, or a first PRACHbandwidth, and a second configuration specifying one or more of a secondPRACH format, a second PRACH length, a second set of PRACH sequences, ora second PRACH bandwidth; and receiving a PRACH communication accordingto one of the first configuration or the second configuration based on amaximum permissible exposure (MPE) condition.
 27. The method of claim26, wherein receiving the PRACH communication comprises: transmitting aparameter of a rule for selecting, based at least in part on the MPEcondition, the first configuration or the second configuration, andreceiving the PRACH communication according to the first configurationor the second configuration.
 28. The method of claim 26, wherein thefirst configuration specifies the first PRACH format, wherein the secondconfiguration specifies the second PRACH format, and wherein the firstPRACH format is reduced in size or a number of fields relative to thesecond PRACH format.
 29. The method of claim 26, wherein the firstconfiguration specifies the first PRACH length, wherein the secondconfiguration specifies the second PRACH length, and wherein the firstPRACH length is shorter than the second PRACH length.
 30. The method ofclaim 26, wherein the first configuration specifies the first set ofPRACH sequences, wherein the second configuration specifies the secondset of PRACH sequences, and wherein the first set of PRACH sequences hasfewer PRACH sequences than the second set of PRACH sequences.